Two Venezuelan military personnel were killed and two others injured Tuesday when a Russian-made helicopter crashed in the South American nation, President Nicolas Maduro said.

"Today we have had a sad and regrettable accident in the state of Lara, with an Mi-17 helicopter with two fatalities and two pilots who are fighting for their lives," Maduro said during a meeting with ministers broadcast on state television.

Emergency responders and military officials work the site of a helicopter crash in Lara, Venezuela that left two military personnel dead
Emergency responders and military officials work the site of a helicopter crash in Lara, Venezuela that left two military personnel dead AFP / Artemio Sequera

It was unclear why the chopper went down, and Maduro has ordered an investigation.

The aircraft burst into flames when it crashed, and the injured pilot and co-pilot were pulled to safety by local residents and laborers.

The Venezuelan army said in a statement that the crash occurred during "a supply mission to border protection bases."